A miniature low-loss wideband dual-mode BPF with harmonic suppression

A miniaturized and low insertion loss (IL) wideband bandpass filter (BPF) using a modified square patch resonator with dual-mode feature is presented in this paper. The proposed dual-mode resonator is composed of a side-slit square patch loaded by two L-shaped open-circuited stubs. Simulated results from the electromagnetic (EM) analysis software and measured results show good agreement and excellent performance over the frequency range, including the 3-dB fractional bandwidth (FBW) up to 34.2%, minimum insertion loss 0.64dB, and the 2^nd harmonic suppression better than 33dB.